My review of the “New York Changing” exhibition that ran a few weeks ago began with a quote from Ansel Adams’s book “Examples: The Making of 40 Photographs,” in which he describes his experience shooting “White House Ruin,” the remains of an Anasazi Indian pueblo village in the niche of a cliff in New Mexico. He wrote of his surprise that he took the picture standing in the exact same spot from which Timothy O’Sullivan had taken a picture 69 years earlier, and went on to discuss the differences between the resulting photographs:

The cliffs are yellowish with dark vertical stripes (natural drainage) from above. The recess in which the ruin stands is shadowed and illuminated chiefly by reflected sky light, which is usually bluish. O’Sullivan, like all photographers of his time, was limited to blue-sensitive emulsions that did not record the red or green portions of the spectrum. … In his photograph the cliff stripes and yellow-red areas were rendered quite dark, and the shadow area of the recess was full of light and detail because of the reflected bluish light. … For my photograph, orthochromatic film (not sensitive to red) would have been superior to panchromatic (sensitive to all colors).

Adams tried to compensate for the difference by using colored filters:

While my print is vigorous and suggests the brilliancy and clarity of the scene, the O’Sullivan photograph conveys more luminosity, enhanced by the warm color of the 1874 print. The combination of the wet-plate emulsions and albumen printing-out paper gave a greater exposure range, but the modern papers have greater density range and “brightness” effect.

Technology matters: It sets the parameters of the possible. Adams, who was very sophisticated about photographic techniques, carefully selected his cameras, lenses, filters, films, processing chemicals, and printing paper to get the results he wanted. In Diane Arbus’s case, these were agonizing decisions fraught with existential ramifications. For any photographer, the characteristics and limitations of the equipment available will be second only to his talent in determining what his pictures look like.

George Gilder’s “The Silicon Eye: How a Silicon Valley Company Aims to Make All Current Computers, Cameras, and Cell Phones Obsolete” (W.W. Norton & Company, 318 pages, $32.95) is the story of the development of the Foveon X3 imaging chip, a chip that is radically different from the ones now used in virtually all cameras, cell phones, surveillance monitors, and other imaging devices – and which is demonstrably superior. The X3 produces truer color rendition and incredibly sharp details, say each individual hair on the face of a cat. Kodachrome and Kodacolor films determined the look of the pictures in most American family photo albums for most of the second half of the 20th century; if Foveon succeeds in marketing the X3 chip, it could have a similar impact on the images produced at the start of the 21st.

Mr. Gilder writes about technology and entrepreneurialism in terms of medieval romance: His scientists and engineers are “paladins,” the problems they face are “dragons,” and the last words of his text are “the continuing quest.” It is as if Wired magazine were written by the author of “Sir Gawain and the Green Knight.” For Mr. Gilder, it is never sociological abstractions that make history or affect economic outcomes, but always and necessarily individual human beings; since he is dealing with cutting-edge technology, the individuals are by definition brilliant, creative, driven, and not infrequently quirky. Gilder brings these people quickly to life, explains their accomplishments in terms that are mostly accessible, and makes their interactions high drama.

The hero of “The Silicone Eye” is Carver Mead, the polymath scientist who shaped the computer age through the 20 companies he helped found, as well as through his legendary classes at the California Institute of Technology. “Listen to the technology: Find out what it is telling you” is the message of his teaching, and those of his students who absorbed this lesson are among the great successes of Silicon Valley. Several of the people indispensable to the development of the X3 were outstanding students who hung around Caltech to be near Mr. Mead and worked with him first at Synaptics, a Mead company that makes most of the touchpads used in laptop computers, and then at Foveon. Mr. Mead’s great long-term fixation has been to design analog computers, and it was his vision of their potential usefulness that held his inspired band of tinkers and dreamers together.

Digital computers break the world down into mathematical abstractions, where reality is understood in binary code: Everything in the universe becomes either one or zero. Analog devices experience the world directly and understand it as having infinite possibilities. Photographic film is an analog because each individual grain of silver can register any degree of light from total darkness to blinding white. The digital imagers in common use today require prisms to break light into its primary components of red, blue, and green, each of which is sensed by individual pixels as either being present or not. The pixels are arranged in tiled groups of four – there are two greens – and the information they gather has to be processed by complex formulas to be reconstituted as a picture.

One of the most memorable characters in Mr. Mead’s band of brothers is the only woman, the vivacious and tragic biologist Misha (Michelle) Mahowald. Her brilliant mapping of the mammalian retina gave the others a blueprint they tried to duplicate in silicon-based analog devices. The X3 imager takes advantage of the fact that red, blue, and green penetrate silicon to different depths. Each pixel has a stack of three sensors that registers how much of all the colors are reaching it. One of the advantages of the X3 is that a 3.6-megapixel chip can gather as much information as a 10-megapixel digital chip. There are other advantages that flow from this design and result in the truer colors and sharper image.

Digital photography is already bigger than film, and getting bigger. Digital imager chips are made by the tens of millions, mostly by Japanese companies. Foveon was late to market its analog X3, perhaps too late to ever be real competition. But the X3 is used in the Sigma SD9 and SD10, high-end professional DSLRs, and when I checked the Digital Photography Review Web site, where owners review photography equipment they have bought, the reports on the X3 were uniformly lyrical: “Stunning prints so sharp you can cut your finger on them.” “SD10 images … have a 3D effect.” “The most crystal clear pictures of any DSLR I have seen.” “Resolution is great, detail is phenomenal.”

So maybe the X3 has a future. If it does, pictures will look different.